Xavier took 3 hours to travel from Country V to Country W at 65 km/h. Then he travelled from Country W to another country at 1.2 times his original speed. 60% of the distance from Country V to Country W is equal to ¹₆ of the distance from Country W to the next country. Find the average speed for the whole journey and express it as a mixed number.
Distance he travelled from Country V to Country W
= 3 x 65
= 195 km

Speed from Country W to another country
= 1.2 x 65
= 78 km/h

60% = ⁶⁰₁₀₀ = ³₃

³₅ Distance from Country V to Country W = ¹₆ Distance from Country W to next country
³₅ Distance from Country V to Country W = ³₁₈ Distance from Country W to next country

5 u = 195
1 u = 195 ÷ 5 = 39

Distance from Country W to the next country
= 18 u
= 18 x 39
= 702 km

Time taken from Country W to the next country
= 702 ÷ 78
= 9 h

Total distance of the whole journey
= 195 + 702
= 897 km

Total time taken for the whole journey = 3 + 9 = 12 h

Average speed of the whole journey
= 897 ÷ 12
= 74 ⁹₁₂
= 74 ³₄ km/h

Answer(s): 74 ³₄ km/h